This invention relates to a multipurpose tool and more particularly to a tool for use in levering materials relative to one another in the renovation and construction of building structures.
When renovating building structures, it is often desirable to take various structures apart, while salvaging as much material as possible for later reuse. This is typically accomplished using various pulling and prying tools, for example a crowbar or a nail puller. A known type of apparatus for removing surface materials from a structural member like a joist comprises an elongate shaft having a forked member at one end thereof. The fork is arranged to straddle the joist, while the shaft serves as a lever for pulling the surface materials from the joist with the fork.
An example of a known apparatus of this type includes U.S. Pat. No. 5,642,591 to Eddie. Eddie provides a multipurpose hand tool apparatus which is used for various tasks related to construction and renovation of building structures. The apparatus includes an elongate shaft having a fork mounted on each end thereof as well and a coupling member mounted centrally on the shaft for securing an end of a chain or a structural member thereto. The forks at each end of the shaft and the coupling spaced therebetween however result in tool which is awkward to handle and difficult to grasp. Furthermore, the penetrating members of the forks are poorly oriented for penetrating through surface materials for generating sufficient leverage force for use in pulling various structural members apart.
The present invention is concerned with certain improvements to multipurpose tools related to levering tools for the purposes of renovating building structures.
According to one aspect of the present invention there is provided a multipurpose tool comprising:
an elongate shaft having a gripping end and a working end; and
at least one elongate blade mounted transversely to the shaft on the working end thereof, the blade having a toe portion extending from the shaft towards a first penetrating end and a heel portion extending from the shaft opposite the toe portion towards a second engaging end of the blade, the blade having an outer side opposite the gripping end of the shaft wherein the outer side of the blade is formed to define at least one fulcrum located thereon between the first and second ends of the blade.
The blades are oriented on the working end of the shaft such that there is a heel portion opposite the toe portion which is useful for providing added leverage when the tool is used as a lever. A person may position the shaft in a generally upright orientation for inserting the toe portion of the blades beneath an object to be lifted. Pulling back on the shaft while stepping on the heel portion of the blades provides a stable lifting arrangement for pivoting the tool about the fulcrum with minimal effort.
According to a second aspect of the present invention there is provided a multipurpose tool comprising:
an elongate shaft having a gripping end and a working end; and
a pair of elongate, spaced apart blades mounted transversely to the shaft on the working end thereof with the shaft therebetween, each blade comprising a plate member extending longitudinally from a first penetrating end to a second engaging end and being oriented such that the plate member lies parallel to the shaft with an outer side of the blade opposite the gripping end of the shaft;
wherein the working end of the shaft is formed to define a fulcrum located between the blades spaced between the first and second ends thereof.
The spaced apart arrangement of the pair of blades allows the blades to be straddled over a joist having surface materials supported thereon. The tool may thus be used to pull the surface materials from the joist by rocking the blades about a fulcrum located therebetween while moving the shaft in a front to back direction. The parallel arrangement of the plates of the blades however, further allows the blades to secure the joist therebetween in a stable arrangement for twisting the joist free by rocking the shaft side to side. Both actions can be accomplished by the working end of the shaft while a person using the tool grips the gripping end.
According to a further aspect of the present invention there is provided a multipurpose tool comprising:
an elongate shaft having a gripping end and a working end; and
at least one elongate blade mounted transversely to the shaft on the working end thereof and extending longitudinally from a first penetrating end to a second engaging end of the blade, the blade having an outer side opposite the gripping end of the shaft wherein the outer side of the blade comprises a plurality of substantially flat surfaces located sequentially along the blade with adjacent ones of the surfaces at an oblique angle to one another such that a fulcrum is defined at an intersection of each pair of adjacent surfaces.
The use of multiple fulcrum points at fixed positions along the outer side of the blades locates the fulcrum as close as possible to first penetrating end of the blades during initial stages of the lift and then gradually displaced the fulcrum towards the second end of the blades as an object engaged thereon is lifted. At each stage of the lift, the fulcrum is held as close as possible to the object until the blades have been sufficiently pivoted so as to provide a gradual lift at a minimal stress to the person using the tool.
The first penetrating end is preferably tapered towards a cutting edge wherein the cutting edge is located in a plane which lies perpendicularly to the shaft. The orientation of the cutting edge assists the blades in being penetrated into a supporting surface as the tool can be operated in an axe-like manner. Orientation of the shaft perpendicularly to the blade further assists the penetration of the blades when used in a chopping action.
The second engaging end is preferably tapered towards a blunt end face which substantially parallel to the shaft. The blunt end face acts as a hammer for use in breaking up materials or for assisting in penetrating a member into a supporting surface.
When there is provided a plurality of fulcrums spaced longitudinally along the outer side of the blade between the first and second ends of the blade, the outer side of the blade preferably comprises a plurality of substantially flat surfaces located sequentially along the blade with adjacent ones of the surfaces at an oblique angle to one another such that a fulcrum is defined at an intersection of each pair of adjacent surfaces.
There may be provided a pair of blades mounted parallel and spaced apart on the working end of the shaft, each blade having a first penetrating end and a second engaging end.
Each blade preferably comprises a plate member which is parallel to the shaft. The pair of blades is thus able to secure a joist or similar structural member therebetween for twisting the member free or for placing the member during construction.
When using a pair of blades, a fulcrum is preferably located between the blades, spaced inwardly from an outer side of the blades with an outer bottom face of the fulcrum located between the blades being spaced outwardly from and below an inner top side of each blade.
There may be provided a plurality of longitudinally spaced apertures located in each blade, the apertures in one of the blades being aligned with corresponding apertures in the other blade. The apertures allow additional materials to be secured to the blades for added leverage or for using the tool in positioning structural members during construction.
The shaft is preferably mounted between the plates such that an inner side of each blade defines a shoulder adjacent a corresponding side of the shaft. The shoulder can thus be used to support structural members thereon with the tool being supported in a free standing position. Pivotal movement of the tool about on the fulcrums will effectively raise the structural member supported thereon for assisting in placing materials during construction.
A width of the penetrating end of each blade is preferably significantly less than a spacing between the pair of blades. When used in a chopping action the overall width of the blade penetration into a supporting surface is thus much greater than the width of each individual blade for minimising resistance to blade penetration.
The fulcrum located between the blades may comprise a drum having an axis which lies perpendicularly to the shaft such that an outer face of the drum defines the fulcrum. The drum is preferably a tubular member having an opening at each end thereof defining a passage therethrough. The drum may thus also be used for receiving elongate materials, for example a bar, therethrough such that the material can be bent as desired by pivoting the tool laterally.
There may be provided flange member extending laterally outward from a side of one blade, the flange member having at least one notch therein for use as a nail puller.
There may further be provided a serrated portion on an inner side of each blade, defining a gripping portion of each blade.